Transmission system with isi channel and method of operating thereof

Abstract

There is provided a transmission system and method of operating thereof. The method comprises: dividing a data sequence to be transmitted into a plurality of data blocks; encoding one or more data blocks with one or more linear systematic cyclic codes thus giving rise to encoded data blocks; transmitting said encoded data blocks over an ISI transmission channel; upon receiving, applying a linear integer-forcing (IF) equalization to the received data blocks; processing the output of the IF equalization thereby detecting for each encoded data block a valid codeword with maximal likelihood of decoding; and reconstructing the data blocks using the respective detected valid codewords.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS[0001]This application relates to and claims priority from U.S. Provisional Patent Application No. 61 / 298,959 filed on Jan. 28, 2010 incorporated herein by reference in its entirety.FIELD OF THE INVENTION[0002]The present invention relates, in general, to methods of digital transmission over communication and / or storage channels and systems thereof, and, more particularly, to digital transmission over ISI channels.BACKGROUND OF THE INVENTION[0003]Modern digital transmission is characterized by growing signaling rates requiring using the maximum possible channel bandwidth. There are numerous known approaches offering a tradeoff between robustness to channel's noise to power level, complexity and delay. Among undesired phenomena, which increase with the growing rate of transmission, is intersymbol interference (ISI). Intersymbol interference is a common practical impairment found in many transmission and storage systems, including voiceband mode...

AI Technical Summary

Benefits of technology

[0021]The transmitter can be further operable to divide a data sequence to be transmitted into a plurality of data blocks such that a number of blocks in the plurality of data blocks corresponds to a target transmission rate, and such that said plurality of data blocks comprises a first set of data blocks and a second set of data blocks. Further the transmitter can be operable to provide encoding merely to the data blocks from the second set, to pad a predefined number of predefined symbols at the end of each data block, wherein padding to the data blocks from the second set is provided before encoding; and to map the data blocks from the first set and the encoded data blocks from the second set to 2M-PAM constellation points with the help of natural labeling. The receiver, accordingly, can be further operable to reduce the output of IF equalization modulo-2 before processing for codeword detection.

[0026]Among advantages of certain embodiments of the presently disclosed subject matter is preventing the phenomena of error propagation. Decoding may be performed before inverting I(D), thus dramatically reducing the error probability.

Problems solved by technology

Intersymbol interference is a common practical impairment found in many transmission and storage systems, including voiceband modems, digital subscriber loop data transmission, storage disks, digital mobile radio channels, digital microwave channels, fiber-optic channels, etc.

ISI is a form of distortion of a signal in which one symbol interferes with subsequent symbols having similar effect as noise, thus making the transmission less reliable.

However, it has some drawbacks: the alphabet size of the transmitted symbols is considerably enlarged, which in turn makes the approach inapplicable to some media, such as, for example, magnetic recording channels.

Furthermore, when channel state information (CSI) is available only at the receiver, bit allocation is precluded, and channel coding and decoding become more difficult, due to the variation of the SNR across subchannels.

The first type usually cancels most of the ISI by roughly inverting the channel, but may suffer from poor performance due to noise enhancement that is a byproduct of the operation.

The second type is optimal in the sense of Minimum Mean Square Error (MMSE) before the symbol-by-symbol decision element, but has problems with combining with a forward error correcting code (FEC).

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